sequenceDiagram
    participant C as Client
    participant S as Server
    participant R as Redis
    participant K as Kafka
    participant SS as Storage Service
    participant P as Postgres DB

    C->>+S: Connect via Websocket
    S->>+SS: HTTP /register
    SS->>+P: Store user nickname
    P-->>-SS: Return user ID
    SS-->>-S: Return user ID
    S->>+R: Fetch last 10 messages from cache
    R-->>-S: Return messages
    S-->>-C: Send last 10 cached messages

    loop Each Message
        C->>+S: Send message
        S->>+R: Cache message
        R-->>-S: Confirm cache update
        S->>+K: Forward message to Kafka
        S-->>-C: Broadcast message to all clients
        K->>+SS: Pass message to Storage Service
        SS->>+P: Store message in Postgres
    end

    note over S: Caches last 10 messages